Responses to reviewer #2 Reviewer 2 has pointed out some important details of the manuscript that need to be clarified in the revised version. They have also made a number of editorial/technical suggestions for improving the manuscript. We appreciate their input and first respond to the 5 ‘General’ comments and then the 41 ‘Technical’ comments that were made. Included at the end of the response letter are the 3 new figures that we propose adding to the supplementary information of the revised manuscript. General comments: 1. It doesn’t really make sense to use uncalibrated 14C ages in the Geological Setting. I suggest that the existing radiocarbon dates from Kelly and Bennike (1992) should be re- calibrated using Marine20 and the same deltaR as the new marine cores. On one hand we agree that it would be helpful to provide re-calibrated dates for the original data presented in Kelly and Bennike (1992). We can do this using the very large dR uncertainty we have adopted in this manuscript, making the published dates directly comparable to our result - these can be included in Table 1. However, in the Introduction/Background we prefer to continue using the raw 14C ages for their samples and refer the reader to Table 1 to see the equivalent calibrated date using Marine20 and our dR uncertainty envelope. Using the raw 14C ages in the main text ensures that the Introduction/background does not become outdated when new constraints on dR for the region emerge. In the Discussion we can report the calibrated age ranges for easier comparison with our data (when needed). Our dR of 300 +/- 300 is designed to provide a robust estimate that covers the ranges in published literature and is useful for dating the lithostratigraphic boundaries in our records. 2) The result section is a mixture of descriptions and interpretations. Example line: 287-288, 299-300, 308-309, 317, 324, 336-338. I suggest to clearly divide the result section into two separate sub-sections: description followed by interpretation. This will allow the reader to assess the data and follow the logic in the interpretations. We can re-organize this section of the results, ending each of the Lithologic Unit descriptions with some of the basic interpretations of the depositional environment. The broader interpretation of the facies succession will remain at the start of the Discussion. 3) Figure 5 offers a great summary of the most important data. It would be really nice to compliment the figure with the CT scans from the suppl. material or the high-resolution picture from the XRF scanner. It is really a pity that the CT scans are hidden in the suppl. material. We agree, and seeing the citation metrics for the article, it is clear that the images in the supplementary material are not being widely viewed. We will introduce a new figure in the manuscript that show the CT-image, lithologic units and location of radiocarbon dates for each core. 4) The way the age of the individual units has been constrained differ from most studies as it uses the min. and max. ages from each unit to define the age range. However, as the radiocarbon dates are not always placed optimally at the boundaries between units this makes it difficult to compare the age ranges of the units between the different cores. I
Welcome message from author
This document is posted to help you gain knowledge. Please leave a comment to let me know what you think about it! Share it to your friends and learn new things together.
Transcript
Responsestoreviewer#2Reviewer2haspointedoutsomeimportantdetailsofthemanuscriptthatneedtobeclarifiedintherevisedversion.Theyhavealsomadeanumberofeditorial/technicalsuggestionsforimprovingthemanuscript.Weappreciatetheirinputandfirstrespondtothe5‘General’commentsandthenthe41‘Technical’commentsthatweremade.Includedattheendoftheresponseletterarethe3newfiguresthatweproposeaddingtothesupplementaryinformationoftherevisedmanuscript.Generalcomments:1.Itdoesn’treallymakesensetouseuncalibrated14CagesintheGeologicalSetting.IsuggestthattheexistingradiocarbondatesfromKellyandBennike(1992)shouldbere-calibratedusingMarine20andthesamedeltaRasthenewmarinecores.
Ononehandweagreethatitwouldbehelpfultoprovidere-calibrateddatesfortheoriginaldatapresentedinKellyandBennike(1992).WecandothisusingtheverylargedRuncertaintywehaveadoptedinthismanuscript,makingthepublisheddatesdirectlycomparabletoourresult-thesecanbeincludedinTable1.However,intheIntroduction/Backgroundweprefertocontinueusingtheraw14CagesfortheirsamplesandreferthereadertoTable1toseetheequivalentcalibrateddateusingMarine20andourdRuncertaintyenvelope.Usingtheraw14CagesinthemaintextensuresthattheIntroduction/backgrounddoesnotbecomeoutdatedwhennewconstraintsondRfortheregionemerge.IntheDiscussionwecanreportthecalibratedagerangesforeasiercomparisonwithourdata(whenneeded).OurdRof300+/-300isdesignedtoprovidearobustestimatethatcoverstherangesinpublishedliteratureandisusefulfordatingthelithostratigraphicboundariesinourrecords.
2)Theresultsectionisamixtureofdescriptionsandinterpretations.Exampleline:287-288,299-300,308-309,317,324,336-338.Isuggesttoclearlydividetheresultsectionintotwoseparatesub-sections:descriptionfollowedbyinterpretation.Thiswillallowthereadertoassessthedataandfollowthelogicintheinterpretations.
Wecanre-organizethissectionoftheresults,endingeachoftheLithologicUnitdescriptionswithsomeofthebasicinterpretationsofthedepositionalenvironment.ThebroaderinterpretationofthefaciessuccessionwillremainatthestartoftheDiscussion.
3)Figure5offersagreatsummaryofthemostimportantdata.ItwouldbereallynicetocomplimentthefigurewiththeCTscansfromthesuppl.materialorthehigh-resolutionpicturefromtheXRFscanner.ItisreallyapitythattheCTscansarehiddeninthesuppl.material.
Weagree,andseeingthecitationmetricsforthearticle,itisclearthattheimagesinthesupplementarymaterialarenotbeingwidelyviewed.WewillintroduceanewfigureinthemanuscriptthatshowtheCT-image,lithologicunitsandlocationofradiocarbondatesforeachcore.
4)Thewaytheageoftheindividualunitshasbeenconstraineddifferfrommoststudiesasitusesthemin.andmax.agesfromeachunittodefinetheagerange.However,astheradiocarbondatesarenotalwaysplacedoptimallyattheboundariesbetweenunitsthismakesitdifficulttocomparetheagerangesoftheunitsbetweenthedifferentcores.I
suggestthatanage-depthmodelforeachsedimentcoreisproduced.Thiswouldmakeitpossibletodeterminetheageattheboundaries(withanuncertainty)andalsoallowforafiguretobemadewheretheproxydata(fromfigure5)isplottedonanagescale.Thisisstandardprocedureanditwouldmakeagreatsupplementtothediscussionsection5.2-5.4.
Althoughwepresentalargenumberofnew14Cdates,wedonothavetheabilitytogeneratemeaningful,continuousagemodelsforeachofthecores.Thevastmajorityofsamplesweinvestigateddidnotcontainenoughforaminiferatoobtainradiocarbondates,sowehavenotbeenabletodateeachcoreattheresolution,orexactdepth,thatwouldwewant.Atthesametime,itisonlyLU5/4andLU1bwherewedonothavedatedsampleswithinafewcentimetersofthelithologicboundary.
Weexpectimprovedagemodelstoemergefromfuturework.Thiscouldcomefrom1)additionalradiocarbondates,2)Improvedconstraintsonthelocalreservoireffect(i.epairedsamples,210Pb,137Cs,tephra),and3)Improvedstratigraphiccorrelationbetweencores,andpotentiallyindependentagecontrol,fromgeneratingpaleosecularvariationrecords–aswasdonebyReillyetal.,2019forPetermannGlacier.Thesemeasurementsareinprogress,andmayallowustostackmoredatesfromthedifferentcoresontoamasterchronology.Therefore,wefeelthatwhileusingthisreallybroaddR,andinlightofnewdatathatshouldsoonemerge,itisnottherighttimetostartgeneratingdetailed,conventionalagemodelsforeachcore.
Westronglyfeelthattheapproachwehavetakenhere,isarobustwaytodatethemajoreventsandenvironmentalchangesthatoccurredthroughtheHolocene.BecausewehaveappliedsuchalargedR,improvedconstraintsondRand/orapplyingabaysianmodelingtechnique,willnarrowtheuncertaintyrangesoftheunitboundaries.Furthermore,sincewepresentourdataasmaximumconstraintsfortheonsetofthedifferentunits(usingtheyoungestdatefromtheunderlyingunit),theywillremaincorrect.However,werecognizethatpresentingmoreconventionalage-depthmodelsissomewhatnecessarytoevaluatesomeoftheindividualages,andelucidatethereasoningbehind‘accepting’or‘rejecting’someofthereturneddates.Inparticular,thereviewerhaslateraskedquestionsregardingwhywerejectedsomedatesfrom10-GCand8-PC.Assuggested,wehavecompiledage-depthfiguresforeachcore(ReviewFig.1),andcanincludethisinthesupplementaryinformation.Whilethesearenotagemodelsperse,theydoillustratethestratigraphicorderingofdatesineachcore,andhowtheyalignwithourproposedunitboundaryages.
Indoingthis,therearetwoimportantinsightswehavedrawnthatwerealizemustbeexplainedbetterintherevisedmanuscript.ThefirstistoexplainwhytheyoungagereturnedfromtheLU3/LU2boundaryin10GCisnotusedtodatethisboundary(comment21byReviewer2below).ThereasonsfornotusingthisdateforthebaseofLU2are1)olderagesthatareinstratigraphicorderarefoundintheothercoresforLU2,2)Thereisstrongevidenceforaperiodoferosion/non-depositionacrosstheboundaryat10GContheoutersill(ReviewFig.2tobeincludedinsupplementarymaterial),and3)Thissamplein10GCcomprised4cmofmaterial(50-54cm),withsomeofthiscomingfromtheoverlyingLU2andsomefrombelowinLU3.Itisnotpossibletoidentifyhowmanyofthedatedspecimenscamefromeachunit.
Thesecondpointwewillmorefullyillustrateanddiscussiswhyweidentifiedthelowestdatein8-PC(nearthebaseofLU5)asanoutlier.Therearetworeasonsforthisthatwewillhighlightintherevisedmanuscript.1)Theagedifferencebetweenthelowesttwodatesin8-PCis1680years,buttheyareonlyseparatedby24.5cm,suggestingthatthelowestmostageistooold,ordepositionwasnotcontinuous,and2)theolder,lowestmostagewasobtainedfromasamplecontainingmixedbenthicforaminfera,whichingeneralseemedtobemorepronetoreturningoldagescomparedtomono-specificsamplesofC.neoteretis.MoreclearlyrecognizingthatsedimentationduringLU5wasnotcontinuousisimportant.Thelaminatedunitclearlycontainsnumerouserosionalzonesofunknownduration,whicharelogicallymorefrequentnearthebaseoftheunit,inwhatweinterpretasagroundingzoneproximalsetting.Wehaveaddedsymbolsindicatingthisonourcompilationof14Cdates(Figure8inoriginalmanuscript),andincludeanadditionaldetailedinterpretedimagecontainingexamplesfrom7-PC,8-PCand9-PCtothesupplementarymaterial(ReviewFigure3).
5)Itisclearthatthemostchallengingunittointerpretisthediamictonunit3.Theunitdiffersfrommostotherunitswhicharelaminated.Itonlyresemblesunit6thelowermostunitwhichisinterpretedassubglacialtill.However,theauthorspreferanalternativeexplanationwhereunit3representsmassiveIRDdepositionduringaperiodwheretheicefrontismostretracted.Theyalsodiscussotherpossibilitiesbutfindthemlesslikely.Iamnotcompletelyconvincedbutagreethatitisdifficulttheinterpretationofunit3isnotstraightforward.Iwonderifunit4insteadcouldrepresenttheperiodwhereRGismostretractedandthatunit3representsthephasewhereitbeginstoreadvancesendingicebergs(IRD)intoSherardOsbornFjordagain.Ifcorrect,theonsetofreadvanceisc.6calkaBPwhichcoincideswiththegeneralcoolingtrendintheAgassizicecorerecord.
Weshouldstartbyclarifyingthatwedonotarguefor‘massiveIRDdeposition’duringLU3–whichimplieshighratesofIRDinput–butratherslowandsustaineddepositionofIRDintheabsenceofsignificantmeltwaterderivedsedimentsthatcontributedtodepositionofLU5,4,2and1.Wethinkthisisclearinthemanuscriptandwantedtoclarifythishere,asweareunsureifthereviewermeant‘rapidlydeposited’whentheysay‘massiveIRDdeposition’.IsitpossiblethatLU4representsthemostretractedphaseofRyderGlacier,andLU3anadvance?Wedonotbelieveso.Onebasicreasonistheoverallfaciessuccession.IfLU3representedare-advance,itbecomeshardtounderstandhowthiscantransitionintopotentiallyseasonallyopenwaterconditions,andgenerallyamelioratedclimateconditions,duringthedepositionofLU2.OurinterpretationisalsoconsistentwithwhathasbeendescribedbyKellyandBennike(1992)basedonmappinganddatingofraisedshorelinesandmorraines.Inparticular,aswestateintheGeologic,oceanographicandglaciologicsetting:“...peatdepositsoverwhichtheicemarginadvancedprovideanageof5100±13014CaBP(Station41),whileatSteensbyGlacier,reworkedmarinemacrofossilsinlateralmorainesyieldanageof4870±8014CaBP(Station34;KellyandBennike,1992).”.CalibratedusingIntcal20andMarine20respectively,theseprovideagesof5830±170calaBP(forthepeat)and4560±410calaBP(forthereworkedmolluscsontopofthelateralmorraines).Thesearemoreconsistentwithourinterpretationthatthere-advanceoccurredduringLU3/LU2.ObviouslythisrequiressomeclarificationintheDiscussionofthemanuscriptwherewewillmorecloselytietheearlierfindingsofKellyandBennike
(1992)toourresults.ProvidingupdatedcalibratedagesinTable1willhelpwiththiscomparison.Importantly,inonesensetherevieweriscorrect,wedonotknowwhenthere-advancebegan.Intherevisedmanuscript,wewillpointoutthattheinitialre-advancelikelybeganduringLU3,butcritically,amarinebasedglacierandicetongueweredefinitelyestablishedbytheonsetofLU2.Thisremainsconsistentwithourinterpretationofthefaciessuccession.
Technicalcomments:1.Line20:ChangetoGreenlandIceSheet.
Thishasbeencorrected.2.Figure1:AddGl.forglacierafterHumboldt,Petermannetc.AlsoaddIceSheetafterGreenland.
Thishasbeencorrected.3.Line43:ChangetoGreenlandIceSheet.
Thishasbeencorrected.4.Line61:ChangetoLastGlacialMaximum.
Thishasbeencorrected.5.Line66:ChangetoMöller.
Thishasbeencorrectedinthemaintextandreferencelist.6.Line75:AddglaciersafterPetermann.
Thishasbeenadded.
7.Line75:ChangetoNioghalvfjerdsfjordGlacier.Thishasbeenadded.
8.Line110:ChangetonorthGreenland.Thishasbeencorrected.
9.Line118:9390+-90dateisnotintable1Thiswasanoversightandthedatehasnowbeenincludedinthetable.
10.Table1:CombinewithTableandcalibratetheoldageswithMarine20.
Wecanincludere-calibratedMarine20datesinthetableusingthesamedRasweapplytomakecomparisonsmorestraightforward.
11.Line127:DeletecalaBPafter>9.5.
Thishasbeencorrected.12.Line129:Marktheice-dammedlakeonthemap.
Toourknowledgethelimitsandextentoftheproposedicedammedlakehavenotbeenmappedout.Forthisreason,wehavenotportrayeditsextentonthefigure.ItisnotclearwhetheritwouldhaveextendedfromSherardOsbornFjordacrosstoVictoriaFjord,oroccupiedamorerestrictedpartofWulffland–whichwouldultimatelydependontheglacier(s)configurationandrelativesealevelatthetimeofitsexistence.
13.Line131:Arethedatedshellsreworkedintothemoraine?Goodquestion.Infactwehadmadeaslighterrorinreportingthestationnamesandmixedupstation36and40.Theproblemisthataclearstationdescriptionisnotavailableforsomeinstances,orhardtointerpretfromthesummaryworkbeKellyandBennike,1992.Wehavegonebacktotheoriginalpublicationsdescribingthedatedmaterial(KellyandBennike,1985,BennikeandKelly,1987),andthesealsodonotprovideaverygoodgeologicalcontextforthesamples.WehaveaddedmoredetailedsamplelocaldescriptionsinTable1,andcorrectedourpreviouserror.Inshort,atstation36,inwesternWarmingLand,thedatedshellswerefrommarinesiltsthatwereyoungerthantheWarmingLandStademorrainesandreturnedandageof8210±12014CaBP(not6480±10014CaBPthatweoriginallywrote).Theageof6480±10014CaBPcamefromshellsfromamarinesiltinfrontofRyderGlacier(Station40)andfromwhatweunderstand,constrainsthetimingforiceretreattowardsthemodernposition.Bennike,O.&Kelly,M.1987:Radiocarbondatingofsamplescollectedduringthe1984expeditiontoNorthGreenland.Rapp.Grønlandsgeol.Unders.135,8-10.Kelly,M.&Bennike,O.1985:QuaternarygeologyofpartsofcentralandwesternNorthGreenland:apreliminaryaccount.Rapp.Grønlandsgeol.Unders.126,111-116.
14.Line136:ChangetoRyderGlacier.
Thishasbeencorrected.
15.Table2:Couldbemovedtosuppl.material.Table2containsthemeta-dataforthecoringstations.Weprefertoleavethetableinthemainpaper,asitisanimportantresourceforfuturestudies.Thosewhowanttolocatethecoresgeographicallyetc,shouldnotneedtodigthroughthesupplementarymaterial.
16.Figure4:Isnotshowingmuchandcouldbemovedtosuppl.material.Onceagain,weprefertokeepthisinthemainmanuscript.Weagreethatamoredetailedassessmentofthesubbottomdatashouldbeundertakeninfuturestudies.However,inthecontextofthismanuscript,thisfigureclearlyillustratesthegeneralthicknessofsedimentsontopofacousticbasement,andhowfarthecorespenetratedintothissedimentarycover.
17.Line167-168:Changelithifiedtocompacted.ThiswasalsosuggestedbyReviewer1,andhasbeenchangedto‘consolidated’.
18.Table3:13Cismissingforsample26.
Wehaveadded‘N/A’tothetable,asthesamplewastoosmalltoprovidea13Cmeasurement.
19.Line268:DeleteglacialafterHolocene.Thishasbeendeleted.
20.Line271:Changethroughtoand.
Thishasbeenchanged.
21.Figure5:On10-GCthe2450dateseemstobewithinunit3butitismarkedasunit2infigure8?
PleaseseeourdetailedresponsetoGeneralcomment4.Essentially,thisdatewasobtainedfroma4-cmthicksamplethatincludedsedimentsfromLU3andLU2,andwebelievethatahiatusexistsbetweentheseunitsatthisspecificstation.
On7-PCthedate7090seemstobeanoutlierbutitisnotmarkedwithred.
Tworeasonsforthis:1)Thetwoagesatthisdepthoverlapat1-sigma.ObvisoulytheywillnotifthedRisreduced,butfornowthiswasabasiccriteriaweappliedtoidentifyoutliers.2)Thetwodatesfromthatintervalarefromaplankticandabenthicsample,andwecannotbesurethatdifferentdRvalueswouldnotresolvetheapparentoffset.Therefore,wehavenotdiscardedeitherdateatthistime.
Also,whatisthesquarenextto7090representing?
Thiswasfromanearlierversionofthefigureandusedtodifferentiatewhetheritwasfromaplankticorbenthicforamsample.Wedidnotmeantocarrythisconventionovertothepublishedmanuscript,andhavemadeallsamplelocationscircles.
Whyisthelastdateincore8-PC/GCanoutlier?PleaseseeourdetailedresponsetoGeneralcomment4.WehaveadjustedourinterpretationandnowusethisagetodatethebaseofLU5,andprovideevidencethatsedimentationontheinnersillduringLU5wasdiscontinuous.22.Figure8:Idon’tunderstandwhythe14Cdatesinthisplothaveanormaldistribution?Alsoseegeneralcomment3.
Inthisfigurewehaveshownthelikelihooddistribution,meanand1-sigmarangeforeachsamplewhencalibratedusingMarine20andadRof300+/-300years.Theyarenotallexactlynormallydistributed,buttheydonohavetheskewnessthatwouldariseifweweremodelingtheagesandshowedaposteriordistribution.Wecanclarifythisinthefigurecaption.
23.Table4:Notimportantandcanbeomittediftheagedepthmodelsassuggestedingeneralcomment4willbemade.
Inlinewithourresponsetogeneralcomment4,weprovidetheseconventional‘age-depth’modelsinthesupplementarymaterial.However,westronglybelievethattheapproachofdatingthelithoistratigraphicboundariesmakesmostsenseatthistime.Anyconventionalagemodelswepublishatthispointwillmostcertainlybere-visedinthenearfuture.AlthoughthiswillreducetheuncertaintyintheagesfortheLU’stheywillverylikelytostaywithinthereportedagerangewehavedefinedbecauseoftheverylargedRwehaveused.
24.Line393:ChangetoNorthernHemisphere.
Thishasbeenchanged.25.Figure9:Reallyniceillustration–aretheradiocarbonagesfromEllesmerere-calibrated?
Yes,theywererecalibratedusingIntcal20.Weshouldhaveindicatedthisinthefigurecaptionandwilldosointherevisedms.
26.Line419:ChangetoMöller.
Thishasbeenchanged.
27.Line423:AddcalkaBPafter12.5.
Thishasbeenchanged.28.Line430:DeleteonelinFullford.
Thishasbeencorrected.29.Line435:ChangetoGrIS. Thishasbeenchanged.30.Figure10.Again,areallygreatillustration.CouldyouaddthelocationsoftheWarmingLandandKapFulfordStadesonthefigure?
Thesehavebeenaddedtothefigure.31.Line466:Itisstatedthat…LU3rangefrom6.3to3.9calkaBP.However,theupperpartofunit3in10-GCis245014CaBP.Whyisthisdateomittedinthesummary?
PleaseseeourdetailedresponsetoGeneralcomment4.32.Line508-510:Temperatureswerenot2.5-4ºCwarmeruntil6.2-6ka.TheywerestillhighbutthepeakwarmthoccurredinthebeginningoftheEarlyHoloceneandwasinsolationdriven.
Wehaveadjustedthissentencetoread:“andpeaklatesummerairtemperaturesinferredfromδ18OofchironomidsinSecretandDeltasølakesthatwere>2oCwarmerthenpresentuntil6.2calkaBP(Axfordetal.,2019;Lasheretal.,2017)”asthisiswhattheyreportintheirwork(seeFig.6inAxfordetal.,2019).
33.Line517:ZekollarimodelssuggestthatatleastpartoftheHansTausenicecapsurvivedtheHTM.
Wewereawareofthis,andhadstatedthatthesoutherndomeoftheicecaphaddisappeared.However,wecanmakethismoreclearbystatin::“Thistimingforglacieradvanceisconsistentwithcoolingseeninlakebasedtemperaturereconstructionsaround4calkaBP(Lasheretal.,2017)andtheoldestestimatedage(3.5to4.0calkaBP)foriceatthebaseofthesoutherndomeofHansTausenicecap,whichhaddisappearedduringtheMiddleHolocene-althoughnorthernpartsoftheicecaphadsurvived(MadsenandThorsteinsson,2001;Landviketal.,2001;Zekollarietal.,2017).”
34.Line520:Changeto:MiddleHolocene.
Thishasbeenchanged.35.Line521:Changeto:GrIS.
Thishasbeenchanged.Figure11:Again,agreatillustration.Maybeconsiderchangingthewhitecolorofthemodernicelimittored.ItwouldalsobegreattogettheKapFuldfordandWarmingLandmorainesonthemaps.
Thesehavebeenaddedtothefigure.36.Line540:or245014CaBP?SeecommentLine466.
WearenowclearinthemanuscriptthatthisageisnotusedtodatethebaseofLU2,becauseweinterpretthatthetransitionfromLU3toLU2at10-GCisnon-conformable.
37.Line564:ChangetoFunderetal.,2011.
Thishasbeencorrected.38.Line585:northGreenland.
Thishasbeencorrected.39.Line600:Søndergaardetal(2020)havepublishedapaperinClimateofthePastonthedeglaciationonInglefieldLand,SmithSoundandnaresStraitthatwouldfitintothediscussion.
Wehaveaddedthisreferencetosection5.3intheDiscussion(5.3MiddleHoloceneinlandretreatandcollapseofRyder’sicetongue)
40.Line601:CanthedifferencesinfjordphysiographyplayaroleinthedifferenttimingofretreatbetweenPetermannandRyderglaciers?SherardOsbornFjordisdeeperandpotentiallymoresusceptibletodynamiciceretreatcomparedtotheshallowerPetermannfjord.
Justbelowthisweargue(lines610-625)thatthephysiographyofSherardOsbornfjordisconducivetoglacierandiceshelfstability.Westatethatthereislittleevidenceforcollapseorsurgeevents,intheformofIRDpulses.Giventheargumentswehavealreadylaidout,wedonotfeeltheneedtobacktrackandsaythephysiographyofthefjordcouldhavebeenakeyfactorinRyder’sretreatfromthecoast.
41.Line650:Changeto:LateHolocene.
Thishasbeencorrected.
Related Documents
